Low comp on the left head on 2003 Lincoln Aviator

I am being advised that I need to have the left head replaced due to low compression to the tune of about $4,700.That is for a 12 month 12,000 mile warranty. Recommend whole engine and don't have price on that yet. I took it in to dealer because of check eng light/real ruff idle. No problem noticed at high speeds. I really don't have the $4,700 and I am hoping maybe some other cheaper issue like sensor or wiring. I am not a mechanic but will try simple maintenance.

If there is low compression and a cylinder head is being recommended, there is likely a faulty valve causing the issue. It is possible that the head could be removed, sent to repair and repaired, then reinstalled for cheaper. It would be a good idea to get a second opinion.

A repair shop should perform a manual compression test, then a cylinder leak down test. This will narrow down the concern to the cylinder in question and the valve in question.

If you were going to drop $4,700, I would spend the extra $1,000 or so and replace the entire engine assembly. I cannot imagine the entire engine assembly costing more than $6,000 installed on this vehicle.

List price on the replacement engine in the book I am referencing is $4,222. That's probably negotiable as well. Labor should be about 17 hours for replacement of the complete assembly, including parts transfer. A dealership trying not to lose the job would negotiate this price to less than $6,000 installed. And for that -- you walk away with a 3 year / 100,000 mile warranty from Ford (I believe)...

You can replace your Lincoln Aviator for less than what they want for the engine repair. Shop around a bit on the craigslist site or similar before you borrow funds to finance a repair. You can borrow financing to replace the vehicle from bank/credit union at lower interest and selling your vehicle in fair condition even if you disclose a need for repair should make up the difference. The motors in the Aviators on average are not typically failing at less than 200K mileage.